Phylogenetic status of Megaraptor namunhuaiquii Novas based on a new specimen from Neuquén, Patagonia, Argentina

Abstract

Abstract. A new specimen of Megaraptornamunhuaiquii was discovered on the north coast of the Barreales lake, Neuquén, Argentina. The material comes from the Portezuelo Formation (Upper Turonian-Lower Coniacian) of the Neuquén Group. The new specimen includes an anterior cervical vertebra, scapula, coracoids, ulna, radius, a complete hand, pubis, two caudal vertebrae with haemal arch, and metatarsal IV. This finding improves the knowledge of this species and offers more information to elucidate its phylogenetic relationships. Megaraptornamunhuaiquii exhibits resemblances with Carcharodontosauridae in some aspects of the cervical and caudal vertebrae, but some other similarities are seen with the basal spinosaurid Baryonyx in the shape of the scapula and coracoid, and pubis shape with Torvosaurus. However, Megaraptor bears several derived characters in the construction of the forelimbs that clearly distinguishes the Patagonian taxon from the theropod taxa mentioned above.